Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 25
Filter
1.
Neth Heart J ; 29(7-8): 383-393, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34125353

ABSTRACT

OBJECTIVE: Recent studies have reported suboptimal up-titration of heart failure (HF) therapies in patients with heart failure and a reduced ejection fraction (HFrEF). Here, we report on the achieved doses after nurse-led up-titration, reasons for not achieving the target dose, subsequent changes in left ventricular ejection fraction (LVEF), and mortality. METHODS: From 2012 to 2018, 378 HFrEF patients with a recent (< 3 months) diagnosis of HF were referred to a specialised HF-nurse led clinic for protocolised up-titration of guideline-directed medical therapy (GDMT). The achieved doses of GDMT at 9 months were recorded, as well as reasons for not achieving the optimal dose in all patients. Echocardiography was performed at baseline and after up-titration in 278 patients. RESULTS: Of 345 HFrEF patients with a follow-up visit after 9 months, 69% reached ≥ 50% of the recommended dose of renin-angiotensin-system (RAS) inhibitors, 73% reached ≥ 50% of the recommended dose of beta-blockers and 77% reached ≥ 50% of the recommended dose of mineralocorticoid receptor antagonists. The main reasons for not reaching the target dose were hypotension (RAS inhibitors and beta-blockers), bradycardia (beta-blockers) and renal dysfunction (RAS inhibitors). During a median follow-up of 9 months, mean LVEF increased from 27.6% at baseline to 38.8% at follow-up. Each 5% increase in LVEF was associated with an adjusted hazard ratio of 0.84 (0.75-0.94, p = 0.002) for mortality and 0.85 (0.78-0.94, p = 0.001) for the combined endpoint of mortality and/or HF hospitalisation after a mean follow-up of 3.3 years. CONCLUSIONS: This study shows that protocolised up-titration in a nurse-led HF clinic leads to high doses of GDMT and improvement of LVEF in patients with new-onset HFrEF.

2.
Eur J Radiol ; 97: 115-118, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29153361

ABSTRACT

PURPOSE: Comparison of radiation doses in patients undergoing angiographic bronchial artery embolization (BAE) before and after a noise reduction imaging technology upgrade. METHODS: We performed a retrospective study of 70 patients undergoing BAE. Procedures were performed before (n=32) and after (n=38) the technology upgrade containing additional filters and improved image-processing. Cumulative air kerma (AK), cumulative dose area product (DAP), number of exposure frames, total fluoroscopy time and amount of contrast agent were recorded. Mean values were calculated and compared using two-tailed t-tests. DSA image quality was assessed independently by two blinded readers and compared using the Wilcoxon signed-rank test. RESULTS: Using the new technology resulted in a significant reduction of 59% in DAP (149.2 (103.1-279.1) vs. 54.8 (38.2-100.7) Gy*cm2, p<0.001) and a significant reduction of 60% for AK (1.3 (0.6-1.9) vs. 0.5 (0.3-0.9) Gy, p<0.001) in comparison to procedures before the upgrade. There was no significant difference between the number of exposure frames in both groups (251±181 vs. 254±133 frames, p=0.07), time of fluoroscopy (28.8 (18.5-50.4) vs. 28.1 (23.3-38.7) min, p=0.73), or the amount of contrast agent used (139.5±70.8 vs. 163.1±63.1ml, p=0.11). No significant difference regarding image quality could be detected (3 (2,3) vs. 3 (2-4), p=0.64). CONCLUSIONS: The new angiographic noise reduction technology significantly decreases the radiation dose during bronchial artery embolization without compromising image quality or increasing time of fluoroscopy or contrast volume.


Subject(s)
Bronchial Arteries/diagnostic imaging , Embolization, Therapeutic/methods , Hemoptysis/therapy , Noise , Adult , Aged , Angiography/methods , Female , Fluoroscopy/methods , Hemoptysis/diagnostic imaging , Humans , Image Processing, Computer-Assisted/methods , Male , Middle Aged , Radiation Dosage , Retrospective Studies
3.
Eur J Radiol ; 86: 284-288, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28027761

ABSTRACT

OBJECTIVE: To compare patient radiation dose in patients undergoing transjugular intrahepatic portosystemic shunt (TIPS) implantation before and after an imaging-processing technology upgrade. METHODS: In our retrospective single-center-study, cumulative air kerma (AK), cumulative dose area product (DAP), total fluoroscopy time and contrast agent were collected from an age- and BMI-matched collective of 108 patients undergoing TIPS implantation. 54 procedures were performed before and 54 after the technology upgrade. Mean values were calculated and compared using two-tailed t-tests. Two blinded, independent readers assessed DSA image quality using a four-rank likert scale and the Wilcoxcon test. RESULTS: The new technology demonstrated a significant reduction of 57% of mean DAP (402.8 vs. 173.3Gycm2, p<0.001) and a significant reduction of 58% of mean AK (1.7 vs. 0.7Gy, p<0.001) compared to the precursor technology. Time of fluoroscopy (26.4 vs. 27.8min, p=0.45) and amount of contrast agent (109.4 vs. 114.9ml, p=0.62) did not differ significantly between the two groups. The DSA image quality of the new technology was not inferior (2.66 vs. 2.77, p=0.56). CONCLUSIONS: In our study the new imaging technology halved radiation dose in patients undergoing TIPS maintaining sufficient image quality without a significant increase in radiation time or contrast consumption.


Subject(s)
Fluoroscopy/methods , Portasystemic Shunt, Transjugular Intrahepatic/methods , Surgery, Computer-Assisted/methods , Female , Fluoroscopy/standards , Humans , Male , Middle Aged , Radiation Dosage , Retrospective Studies
4.
Internist (Berl) ; 56(5): 566-72, 2015 May.
Article in German | MEDLINE | ID: mdl-25874738

ABSTRACT

A 73-year-old female patient who had received a liver and kidney transplantation presented with symptomatic pancytopenia and right-sided upper abdominal pain. The histological investigation of a bone marrow biopsy showed the extremely rare manifestation of a disseminated Merkel cell carcinoma with infiltration of the bone marrow and suppression of hematopoiesis. Also a Coombs test positive hemolytic anemia did not show a significant response to high-dose steroid therapy. Palliative chemotherapy with carboplatin and etoposide at reduced dosage had to be terminated due to deterioration of the patient's general condition. The patient died 2 days after initiation of chemotherapy.


Subject(s)
Abdominal Pain/etiology , Carcinoma, Merkel Cell/diagnosis , Carcinoma, Merkel Cell/etiology , Epistaxis/etiology , Kidney Transplantation/adverse effects , Liver Transplantation/adverse effects , Aged , Antineoplastic Agents/therapeutic use , Carcinoma, Merkel Cell/drug therapy , Combined Modality Therapy/adverse effects , Diagnosis, Differential , Epistaxis/diagnosis , Fatal Outcome , Female , Humans , Recurrence
5.
Rofo ; 186(6): 598-605, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24347356

ABSTRACT

PURPOSE: To assess liver remnant volume regeneration and maintenance, and complications in the long-time follow-up of donors after living donor liver transplantation using CT and MRI. MATERIALS AND METHODS: 47 donors with a mean age of 33.5 years who donated liver tissue for transplantation and who were available for follow-up imaging were included in this retrospective study. Contrast-enhanced CT and MR studies were acquired for routine follow-up. Two observers evaluated pre- and postoperative images regarding anatomy and pathological findings. Volumes were manually measured on contrast-enhanced images in the portal venous phase, and potential postoperative complications were documented. Pre- and postoperative liver volumes were compared for evaluating liver remnant regeneration. RESULTS: 47 preoperative and 89 follow-up studies covered a period of 22.4 months (range: 1 - 84). After right liver lobe (RLL) donation, the mean liver remnant volume was 522.0 ml (±â€Š144.0; 36.1 %; n = 18), after left lateral section (LLS) donation 1,121.7 ml (±â€Š212.8; 79.9 %; n = 24), and after left liver lobe (LLL) donation 1,181.5 ml (±â€Š279.5; 72.0 %; n = 5). Twelve months after donation, the liver remnant volume were 87.3 % (RLL; ±â€Š11.8; n = 11), 95.0 % (LS; ±â€Š11.6; n = 18), and 80.1 % (LLL; ±â€Š2.0; n = 2 LLL) of the preoperative total liver volume. Rapid initial regeneration and maintenance at 80 % of the preoperative liver volume were observed over the total follow-up period.  Minor postoperative complications were found early in 4 patients. No severe or late complications or mortality occurred. CONCLUSION: Rapid regeneration of liver remnant volumes in all donors and volume maintenance over the long-term follow-up period of up to 84 months without severe or late complications are important observations for assessing the safety of LDLT donors. KEY POINTS: Liver remnant volumes of LDLT donors rapidly regenerated after donation and volumes were maintained over the long-term follow-up period of up to 84 months without severe or late complications.


Subject(s)
Liver Regeneration/physiology , Liver Transplantation , Liver/pathology , Living Donors , Magnetic Resonance Imaging , Postoperative Complications/diagnosis , Tomography, X-Ray Computed , Adult , Female , Follow-Up Studies , Humans , Male , Middle Aged , Organ Size/physiology , Patient Safety , Young Adult
6.
Rofo ; 183(7): 641-4, 2011 Jul.
Article in German | MEDLINE | ID: mdl-21391175

ABSTRACT

PURPOSE: To determine the practicability and outcome of fluoroscopic-guided primary one-step treatment of percutaneous gastrostomy (PG) with the system Freka® Gastro Tube (Fresenius Kabi, Germany). MATERIALS AND METHODS: In 39 patients (mean age 62.7 ± 12.0 years), primary PG was performed based on clinical indication from August 2009 to April 2010. The intervention was performed by an experienced radiologist under aseptic conditions by direct puncture with Freka® Gastro Tube under fluoroscopic guidance. The clinical data and outcome as well as any complications originated from the electronic archive of the University Medical Center Hamburg-Eppendorf. RESULTS: The intervention was technically successful in all 39 patients. Within the mean follow-up time of 155.3 ± 73.6 days, 29 patients (74.4 %) did not experience complications. 10 patients (25.6 %) had to be revised. Complications manifested after a mean of 135.6 ± 61.2 days and mainly corresponded to accidental dislocation (50 %). One patient had to be surgically revised under suspicion of a malpositioned tube and suspected intestinal perforation. Clinically relevant wound infections were not detected. The total costs per patient were 553.17 € for our single-step treatment (OPS 5 - 431.x) vs. 963.69 € (OPS 5 - 431.x and OPS 8 - 123.0) for the recommended two-step treatment. CONCLUSION: Fluoroscopic-guided primary single-step treatment with Freka® Gastro Tube system is feasible and not associated with an increased complication rate when compared to published literature applying a two-step treatment approach. Material costs as well as human and time resources could be significantly reduced using the single-step treatment.


Subject(s)
Catheters, Indwelling , Fluoroscopy/instrumentation , Gastrostomy/instrumentation , Minimally Invasive Surgical Procedures/instrumentation , Aged , Catheters, Indwelling/economics , Costs and Cost Analysis , Equipment Design , Female , Fluoroscopy/economics , Follow-Up Studies , Gastrostomy/economics , Humans , Male , Middle Aged , Minimally Invasive Surgical Procedures/economics , National Health Programs/economics , Reoperation/economics
7.
Neth Heart J ; 18(5): 260-3, 2010 May.
Article in English | MEDLINE | ID: mdl-20505800

ABSTRACT

Chronic heart failure is a clinical syndrome with a high mortality and morbidity. Despite optimal therapy, five-year survival is still only 50%. Central sleep apnoea syndrome is seen in approximately 40% of patients with congestive heart failure. Sleep apnoea syndrome can be divided into two forms in these patients: obstructive sleep apnoea syndrome (OSAS) and central sleep apnoea syndrome (CSAS, Cheyne-Stokes respiration), of which CSAS is the most common. CSAS is a form of sleep apnoea in congestive heart failure which is driven by changes in pCO(2). As a consequence of apnoea-hypopnoea an imbalance in myocardial oxygen delivery/consumption ratio will develop, sympathetic and other neurohormonal systems will be activated and right and left ventricular afterload will be increased. Sleep apnoea is associated with an increased mortality in patients with systolic heart failure. Treatment of sleep apnoea increases left ventricular ejection fraction and transplant-free survival. Because of its high prevalence, poor quality of life, poor outcome, and the beneficial effects of treatment, physicians treating patients with heart failure should be aware of central sleep apnoea. There are different treatment options, but the exact effects and indications of each option have not yet been fully determined. Further studies should be done to further investigate its prevalence, and to establish the most adequate therapy for the individual patient. (Neth Heart J 2010;18:260-3.).

8.
Rofo ; 181(10): 970-8, 2009 Oct.
Article in German | MEDLINE | ID: mdl-19517336

ABSTRACT

PURPOSE: To evaluate the changes in academic quality indicators after implementation of a quality management system according to DIN ISO 9001:2000. MATERIALS AND METHODS: After implementation and certification of a quality management system, the actual state based on quality indicators from the fields of student teaching, research, continuing education and the satisfaction of referring physician was determined. After implementation of an action plan for the individual areas, the temporal changes in the ratios were documented in the follow-up. RESULTS: The evaluation of teaching performance obtained by questionnaire among the students of the radiology course showed a steady increase in satisfaction (mean value 2003: 2.7; 2007: 3.9). In the field of research an increase in scientific output was achieved based on the number of an internal publication score (2002: 99 points; 2006: 509). Repeated opinion surveys among our referring physicians found improvements in indicators for the appointment of investigations, consulting service and waiting times for the investigation, while the waiting times for internal transport service did not improve. Exemplary measurements of the success of the advanced training of the staff demonstrated the need for continuing education for quality improvement. CONCLUSION: The evaluation of quality indicators showed over time a measurable positive impact on processes of a radiological University Hospital after implementation of a QM system according to DIN ISO 9001:2000.


Subject(s)
Certification/organization & administration , Hospitals, University/organization & administration , Quality Indicators, Health Care/organization & administration , Radiology Department, Hospital/organization & administration , Total Quality Management/organization & administration , Certification/legislation & jurisprudence , Certification/standards , Education, Medical, Continuing/legislation & jurisprudence , Education, Medical, Continuing/organization & administration , Education, Medical, Continuing/standards , Education, Medical, Graduate/legislation & jurisprudence , Education, Medical, Graduate/organization & administration , Education, Medical, Graduate/standards , Germany , Guidelines as Topic/standards , Health Plan Implementation/legislation & jurisprudence , Health Plan Implementation/organization & administration , Health Plan Implementation/standards , Hospitals, University/legislation & jurisprudence , Hospitals, University/standards , Humans , Publishing/legislation & jurisprudence , Publishing/organization & administration , Publishing/standards , Quality Indicators, Health Care/legislation & jurisprudence , Quality Indicators, Health Care/standards , Radiology/education , Radiology/organization & administration , Radiology Department, Hospital/legislation & jurisprudence , Radiology Department, Hospital/standards , Reference Standards , Referral and Consultation/legislation & jurisprudence , Referral and Consultation/organization & administration , Referral and Consultation/standards , Surveys and Questionnaires , Total Quality Management/legislation & jurisprudence , Total Quality Management/standards , Waiting Lists
9.
Rofo ; 179(12): 1264-71, 2007 Dec.
Article in German | MEDLINE | ID: mdl-18004693

ABSTRACT

PURPOSE: Detailed anatomic information of the left atrium is necessary for securely performing radiofrequency ablation of atrial fibrillation-triggering ectopies in the pulmonary vein ostia. In this study the impact of a preinterventionally acquired cardiac computed tomography (CT) on pulmonary vein isolation (PVI) was assessed. MATERIALS AND METHODS: Examinations of 54 patients with paroxysmal atrial fibrillation undergoing PVI were analyzed. In 27 patients a supplementary cardiac CT was obtained prior to PVI (CT group, 12 women, 15 men, 59.7+/-9.9 years of age): 16 x 1.5 mm collimation, 0.2 pitch, 120 kV tube voltage, 400 effective mAs. The fluoroscopy time, effective dose and quantity of radiofrequency (RF) pulses of the following catheter ablation were compared to 27 patients undergoing stand-alone PVI (11 women, 16 men, 62.0+/-9.9 years of age). Mann-Whitney tests served for statistical comparison. RESULTS: CT datasets were successfully integrated into the ablation procedure of each patient in the CT group. The mean quantity of RF pulses was significantly lower in the CT group (22.1+/-8.0 vs. 29.1+/-11.9, p=0.030), and a significant reduction of fluoroscopy time was found (41.8+/-12.0 min vs. 51.2+/-16.0 min, p=0.005). Effective doses of the catheter ablation differed in an equivalent dimension but altogether not significantly (14.9+/-10.0 mSv vs. 20.0+/-16.0 mSv, p=0.203). The mean additive effective dose of the cardiac CT was 8.5+/-0.3 mSv. CONCLUSION: CT-guided ablation of atrial fibrillation requires less fluoroscopy time than stand-alone PVI. Due to the multi-faceted dependency of individual fluoroscopy doses, a consistent reduction of the effective dose was not observed. Since supplementary CT constitutes an additive dose, optimized CT atriography needs to be designed in order to provide sufficient image quality while reducing X-ray exposure. The reduction in RF pulses implies an increase in the effectiveness and safety of catheter ablation.


Subject(s)
Atrial Fibrillation/diagnostic imaging , Atrial Fibrillation/surgery , Catheter Ablation , Fluoroscopy , Heart Atria/diagnostic imaging , Pulmonary Veins/diagnostic imaging , Pulmonary Veins/surgery , Tomography, X-Ray Computed , Aged , Female , Humans , Imaging, Three-Dimensional , Male , Middle Aged , Radiation Dosage , Statistics, Nonparametric , Tomography, X-Ray Computed/methods
10.
Rofo ; 179(1): 21-30, 2007 Jan.
Article in German | MEDLINE | ID: mdl-17203440

ABSTRACT

Contrast-enhanced MRI using the delayed-enhancement technique (DE-MRI) is widely applied in the clinical work-up of myocardial diseases. Myocardial diseases of varying etiology result in myocardial changes, such as necrosis, fibrosis, edema and metabolite deposition, which can be visualized by DE-MRI. Acute and chronic ischemic diseases based on a coronary artery disease as well as non-ischemic cardiomyopathies display DE. Cardiomyopathies often show a characteristic enhancement pattern. While ischemic lesions are localized in the subendocardium, non-ischemic cardiomyopathies often display an intramyocardial or subepicardial pattern. The typical pattern for dilated cardiomyopathies is band-like and intramyocardial with septal involvement. Arrhythmogenic right-ventricular dysplasias/cardiomyopathies are frequently associated with right-ventricular DE. In the case of amyloid cardiomyopathies which are often restrictive cardiomyopathies, subendocardial and circular DE is typically observed. Hypertrophic cardiomyopathies display patchy intramyocardial DE usually in the anteroseptal region. Acute myocarditis is typically accompanied by intramyocardial or subepicardial DE affecting the lateral wall. In the case of chronic myocarditis, intramyocardial or subepicardial DE is observed most frequently. Cardiac sarcoidosis typically entails patchy subepicardial DE with right- and left-ventricular involvement. Since there is an overlap between the enhancement patterns of cardiomyopathies, the diagnostic accuracy of DE-MRI is limited and the diagnosis must be based on additional clinical and MRI findings. The amount of DE often corresponds with cardiac functional parameters as well as with the frequency of cardiac events so that DE-MRI may be useful for risk stratification. Furthermore, DE-MRI can be helpful in the planning and evaluation of myocardial biopsies and electrophysiological examinations.


Subject(s)
Cardiomyopathies/diagnosis , Magnetic Resonance Imaging/methods , Acute Disease , Adolescent , Adult , Aged , Amyloidosis/diagnosis , Arrhythmogenic Right Ventricular Dysplasia/diagnosis , Cardiomyopathy, Dilated/diagnosis , Cardiomyopathy, Hypertrophic/diagnosis , Cardiomyopathy, Restrictive/diagnosis , Chronic Disease , Contrast Media , Diagnosis, Differential , Female , Gadolinium DTPA , Humans , Magnetic Resonance Imaging, Cine/methods , Male , Middle Aged , Myocarditis/diagnosis , Risk Assessment , Sarcoidosis/diagnosis
11.
Rofo ; 178(10): 1022-7, 2006 Oct.
Article in German | MEDLINE | ID: mdl-17021981

ABSTRACT

PURPOSE: The study was performed to assess the necessity of dose adjustment (kV or mAs (eff.)) in 16-slice CT (MDCT) in postoperative controls of iliosacrally inserted osteosynthetic screws (OS) on preserved human cadaver specimens. The minimal tube settings for diagnostic imaging of the pelvic bone were analyzed and the effective doses and important organ doses were calculated. MATERIALS AND METHODS: 16 preserved human cadaver specimens with transiliac osteosynthetic screws were scanned on a 16-slice CT (collimation 16 x 0.75 mm, pitch 0.7) with 10 different tube settings (35, 50, 75, 100, 150 mAs (eff.) and 120 and 140 kV). 32 datasets (blinded for name and scan parameters) with and without OS were independently evaluated by four observers. The 10 series were sorted by subjective image quality (image noise, contours, artifacts), and the series with the lowest but still diagnostic quality was selected. The statistical analysis included multi-rater-kappa-test and Wilcoxon test for paired samples. RESULTS: The multi-reader agreements for sorting the series were fair (kappa = 0.38). The agreements in comparing the lowest diagnostic image qualities were slight to fair (kappa = 0.08-0.23). The paired sample test comparing the lowest diagnostic image quality with and without OS showed no statistical significance (p = 0.29). 87.5 % of the readouts (n = 64 [16 examinations, 4 readers]) with OS and 78.1 % of those without OS could be adequately diagnosed using the three series with the lowest effective doses (0.9-1.4 mSv for men, 1.4-2.0 mSv for women; 120 kV-35 mAs (eff.), 120-50, 140-35). CONCLUSION: MSCT scans of the pelvic bone can be performed with very low effective doses. It is not necessary to adjust tube settings when imaging bones with osteosynthetic screws. If the concept for the control of the pelvic osteosynthetic screw position includes more than 2 conventional films (for example anterioposterior view with additional inlet and outlet views), a low dose CT is preferable to conventional radiography.


Subject(s)
Bone Screws , Ilium/diagnostic imaging , Pelvis/diagnostic imaging , Radiographic Image Enhancement/methods , Sacrum/diagnostic imaging , Tomography, X-Ray Computed/methods , Animals , Dose-Response Relationship, Radiation , Ilium/surgery , In Vitro Techniques , Reproducibility of Results , Sacrum/surgery , Sensitivity and Specificity , Tissue Preservation , Tomography, X-Ray Computed/instrumentation
12.
Rofo ; 177(8): 1084-92, 2005 Aug.
Article in German | MEDLINE | ID: mdl-16021540

ABSTRACT

PURPOSE: Minimal invasive direct coronary artery bypass grafting (MIDCAB) or off-pump coronary artery bypass grafting (OPCAB) on the beating heart with full or mini-sternotomy are becoming more common in coronary bypass surgery of the left anterior descending (LAD). In the decision, which surgical approach (MIDCAB, OPCAB or conventional surgery with cardiopulmonary bypass) will be best used, knowledge of the anatomical field is of major importance. The aim of the study was to evaluate retrospective ECG-gated 4-row multidetector CT (MDCT) in patients planned for MIDCAB as additional imaging to coronary angiography. MATERIAL AND METHODS: The study included 25 consecutive patients. MSCT was performed as unenhanced (collimation 4 x 2.5 mm) and contrast-enhanced examination (140-170 ml, 300 mg Iodine/ml, collimation 4 x 1 mm). The evaluation included presence of LAD calcifications, distance of LAD and left internal mammarian artery (LIMA), course of LAD and LIMA, the presence or absence of bridging through myocardium or epicardial fat and the presence of pleural fibrosis. The MDCT results were correlated with intra-operative findings. RESULTS: All MDCTs could be assessed with reference to the demands. In 20/25 operations, MDCT had direct influence as to the selection of the surgical approach (11 MIDCAB, 7 OPCAB with mini-sternotomy and 5 with full sternotomy, 2 conventional surgeries). The distance of LAD and LIMA varied from 0.9 to 4.5 cm in MDCT. As to calcifications, 3/25 correlated patients had calcifications and 10 patients had no calcifications in the middle LAD. Seven patients had intraoperative fibrosis of the vessel wall without calcification of the middle LAD, which could not be detected with MDCT. Another 5 patients had single calcified plaques in the middle LAD, 4 of these had a fibrosis of the vessel and 1 had a normal vessel at surgery. In these cases, the anastomosis was done between the calcified plaques. No myocardial bridging was detected by MDCT and at surgery. Bridging of epicardial fat was shown by MDCT and at surgery in 9/25 patients and was excluded in 15 patients. In 1 patient, the LAD seemed to run superficially in MDCT, but was covered with fat as seen during surgery. The course of the LIMA was inconspicuous in all cases, no pleural fibrosis was found. CONCLUSIONS: The 4-row MDCT has proven to be adequate in addition to coronary angiography for preoperative evaluation in patients scheduled for MIDCAB and provides the surgeon with relevant information for the selection of the operative approach.


Subject(s)
Coronary Artery Bypass/methods , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/surgery , Minimally Invasive Surgical Procedures/methods , Preoperative Care/methods , Radiographic Image Enhancement/methods , Surgery, Computer-Assisted/methods , Aged , Aged, 80 and over , Contrast Media , Electrocardiography/instrumentation , Electrocardiography/methods , Female , Humans , Male , Middle Aged , Patient Selection , Preoperative Care/instrumentation , Prognosis , Radiographic Image Enhancement/instrumentation , Retrospective Studies , Transducers , Treatment Outcome
13.
Rofo ; 176(11): 1676-82, 2004 Nov.
Article in German | MEDLINE | ID: mdl-15497087

ABSTRACT

PURPOSE: To evaluate the image quality of thin-section MSCT examinations of low-contrast objects such as liver lesions, and to find out whether a thin slice technique requires an increase in radiation dose. MATERIALS AND METHODS: MSCT examinations of the liver were performed in the portal venous phase on a Volume Zoom Scanner (Siemens, Erlangen) with a collimation of 4 x 2.5 mm, 120 kV, 125 mAs and table speed of 12.5 mm. Forty small hypodense liver lesions with a mean size of 3 mm (1 to 8 mm) were reconstructed using a slice thickness of 3, 5, 7, and 10 mm. All lesions were evaluated for each slice thickness by 3 independent radiologists using a 5-point scale (excellent to poor) for the following 7 criteria: contrast, demarcation and contour of the lesion, image noise and quality, demarcation of liver veins and liver contour. The mean values of the reviewers' scores were calculated. The correlation of the three observers in the evaluation of the criteria was determined using the Kendall's Tau coefficient. RESULTS: The 3-mm thin sections were excellent in the evaluation of lesion detection, lesion contrast and lesion contour with a mean score of 1.4 compared to 4.1 for 10-mm sections. Concerning the criteria image quality and liver contour, thin sections achieved the best results in our series. Image noise was pronounced in thin sections but did not affect negatively the image analysis. Interrater agreement was 0.53 for the criterium image noise. CONCLUSION: Thin sections in MSCT examinations of low contrast objects such as liver lesions do not require an increase in radiation dose because the increase in image noise is compensated by improved lesion contrast.


Subject(s)
Liver Diseases/diagnostic imaging , Tomography, X-Ray Computed/methods , Contrast Media , Humans , Image Processing, Computer-Assisted , Radiation Dosage
14.
Surg Radiol Anat ; 26(3): 239-44, 2004 Jun.
Article in English | MEDLINE | ID: mdl-14968265

ABSTRACT

In modern surgical and transplantation procedures the recognition of anatomic vascular abnormalities of the hepatic arteries is of greater importance than ever. The purpose of this study was to evaluate and classify these variations with respect to their impact on visceral surgery. A total of 604 selective celiac and superior mesenteric angiographies performed on patients with known or suspected liver cirrhosis or hepatic or pancreatic malignancies and on donors of partial liver grafts were analyzed retrospectively. The vascular anatomy of the liver was classified according to different established systems and with particular attention to rare variations. Hepatic arterial anatomy as considered normal in textbook descriptions was found in 79.1%, an aberrant or accessory left hepatic artery (LHA) arising from the left gastric artery in 3.0% and an aberrant or accessory right hepatic artery (RHA) branching off the superior mesenteric artery in 11.9% of the cases. In 1.4% of the cases there was a combination of anomalies of both the LHA and RHA. Variants of the celiac trunk, double hepatic arteries branching at the celiac trunk or hepatic arteries arising directly from the aorta, occurred in 4.1% of the cases. Further atypical branches of the LHA and RHA were found in 0.5% of the cases. Since the incidence and pattern of different types of hepatic arterial anatomy can require specialized preoperative diagnostic as well as intraoperative strategies, knowledge of these abnormalities and their frequency is of major importance for the surgeon as well as the radiologist.


Subject(s)
Celiac Artery/diagnostic imaging , Hepatic Artery/diagnostic imaging , Mesenteric Artery, Superior/diagnostic imaging , Angiography , Aorta, Abdominal/diagnostic imaging , Celiac Artery/abnormalities , Constriction, Pathologic/diagnostic imaging , Hepatic Artery/abnormalities , Humans , Liver Cirrhosis/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Liver Transplantation/diagnostic imaging , Pancreatic Neoplasms/diagnostic imaging , Peripheral Vascular Diseases/diagnostic imaging , Retrospective Studies , Stomach/blood supply , Tissue Donors
15.
Rofo ; 175(2): 258-61, 2003 Feb.
Article in German | MEDLINE | ID: mdl-12584628

ABSTRACT

PURPOSE: The transjugular liver biopsy is performed in patients with coagulopathy to evaluate diffuse hepatopathies. Using a jugular venous access, a liver vein is cannulated and a transvascular biopsy taken. The two techniques in use are the aspiration biopsy with a modified 15G or 16G Ross needle used for TIPS and the core biopsy with a Trucut needle. The sampling is quite similar for these techniques, but the costs are significantly different. This study is a meta-analysis of data published on both techniques to search for clinical evidence that justifies the use of the more expensive Trucut needle or that finds aspiration with the less expensive Ross needle equivalent. MATERIALS AND METHODS: The study includes 16 publications that were published between 1996 and 2002 and provided reliable information on technical success rate, complications and adequate histology. The data on 1374 procedures were analyzed, comprising 436 aspiration biopsies and 938 Trucut biopsies. RESULTS: Considering both procedures together, 95.9 % of the procedures were technically successful and 92.2% of the histologic samples diagnostically adequate. The technical success rate was 96.7 % for the Trucut-biopsies and 94.4 % for the aspiration biopsies. The corresponding rates of obtaining diagnostically adequate histologic samples were 92.5 % and 91.5 %, respectively. The complication rate of the entire population studied was 0.65 % without significant difference found between the two methods. With a list price of 420 Euro, the Trucut system costs about 200 Euro more than the Ross needle, which is listed as approximately 220 Euro. CONCLUSION: In the absence of any significant differences between both techniques for transjugular liver biopsies, economic considerations make the aspiration biopsy with the modified Ross needle preferable over the Trucut needle biopsy.


Subject(s)
Biopsy, Needle/instrumentation , Hepatic Veins , Liver Diseases/pathology , Equipment Design , Equipment Safety , Humans , Jugular Veins , Liver/pathology , Needles
16.
Rofo ; 174(12): 1551-8, 2002 Dec.
Article in German | MEDLINE | ID: mdl-12471528

ABSTRACT

PURPOSE: Evaluation of TSE- and T 1 -3D-GRE-sequences for focal cartilage lesions in vitro in comparison to ultrahigh resolution multi-slice CT. MATERIALS AND METHODS: Forty artificial cartilage lesions in ten bovine patellae were immersed in a solution of iodinated contrast medium and assessed with ultrahigh resolution multi-slice CT. Fat-suppressed TSE images with intermediate- and T 2 -weighting at a slice thickness of 2, 3 and 4 mm as well as fat-suppressed T 1 -weighted 3D-FLASH images with an effective slice thickness of 1, 2 and 3 mm were acquired at 1.5 T. After adding Gd-DTPA to the saline solution containing the patellae, the T 1 -weighted 3D-FLASH imaging was repeated. RESULTS: All cartilage lesions were visualised and graded with ultrahigh resolution multi-slice CT. The TSE images had a higher sensitivity and a higher inter- and intraobserver kappa compared to the FLASH-sequences (TSE: 70 - 95 %; 0.82 - 0.83; 0.85 - 0.9; FLASH: 57.5 - 85 %; 0.53 - 0.72; 0.73 - 0.82, respectively). An increase in slice thickness decreased the sensitivity, whereby deep lesions were even reliably depicted on TSE images at a slice thickness of 3 and 4 mm. Adding Gd-DTPA to the saline solution increased the sensitivity by 10 % with no detectable advantage over the T 2 -weighted TSE images. CONCLUSION: TSE sequences and application of Gd-DTPA seemed to be superior to T 1 -weighted 3D-FLASH sequences without Gd-DTPA in the detection of focal cartilage lesions. The ultrahigh resolution multi-slice CT can serve as in vitro reference standard for focal cartilage lesions.


Subject(s)
Cartilage Diseases/diagnosis , Cartilage, Articular/pathology , Magnetic Resonance Imaging , Tomography, X-Ray Computed/methods , Animals , Cartilage Diseases/diagnostic imaging , Cattle , Gadolinium DTPA , In Vitro Techniques , Patella , Reference Standards , Sensitivity and Specificity
17.
Plant J ; 15(4): 489-500, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9753774

ABSTRACT

To study the regulation of fructan synthesis in plants, we isolated two full-size cDNA clones encoding the two enzymes responsible for fructan biosynthesis in Jerusalem artichoke (Helianthus tuberosus): 1-sucrose:sucrose fructosyl transferase (1-SST) and 1-fructan:fructan fructosyl transferase (1-FFT). Both enzymes have recently been purified to homogeneity from Jerusalem artichoke tubers (Koops and Jonker (1994) J.Exp.Bot.45, 1623-1631; Koops and Jonker (1996) Plant Physiol. 110, 1167-1175) and their amino acid sequences have been partially determined. Using RT-PCR and primers based on these sequences, specific fragments of the genes were amplified from tubers of Jerusalem artichoke. These fragments were used as probes to isolate the cDNAs encoding 1-SST and 1-FFT from a tuber-specific lambdal ZAP library. The deduced amino acid sequences of both cDNAs perfectly matched the sequences of the corresponding purified proteins. At the amino acid level, the cDNA sequences showed 61% homology to each other and 59% homology to tomato vacuolar invertase. Based on characteristics of the deduced amino acid sequence, the first 150 bp of both genes encode a putative vacuolar targeting signal. Southern blot hybridization revealed that both 1-SST and 1-FFT are likely to be encoded by single-copy genes. Expression studies based on RNA blot analysis showed organ-specific and developmental expression of both genes in growing tubers. Lower expression was detected in flowers and in stem. In other organs, including leaf, roots and dormant tubers, no expression could be detected. In tubers, the spatial and developmental expression correlates with the accumulation of fructans. Using the 1-sst and 1-fft cDNAs, chimeric genes were constructed driven by the CaMV 35S promoter. Analysis of transgenic petunia plants carrying these constructs showed that both cDNAs encode functional fructosyltransferase enzymes. Plants transformed with the 35S-1-sst construct accumulated the oligofructans 1-kestose (GF2), 1,1-nystose (GF3) and 1,1,1-fructosylnystose (GF4). Plants transformed with the 35S-1-fft construct did not accumulate fructans, probably because of the absence of suitable substrates for 1-FFT, i.e. fructans with a degree of polymerization > or = 3 (GF2, GF3, etc.). Nevertheless, protein extracts from these transgenic plants were able to convert GF3, when added as a substrate into fructans with a higher degree of polymerization. Progeny of crosses between a 35S-1-sst-containing plant and a 35S-1-fft-containing plant, showed accumulation of high-molecular-weight fructans in old, senescent leaves. Based on the comparison of the predicted amino acid sequences of 1-sst and 1-fft with those of other plant fructosyl transferase genes, we postulate that both plant fructan genes have evolved from plant invertase genes.


Subject(s)
Fructans/biosynthesis , Helianthus/genetics , Hexosyltransferases/genetics , Plant Proteins , Amino Acid Sequence , Cloning, Molecular , Crosses, Genetic , DNA, Complementary/genetics , DNA, Plant , Gene Dosage , Gene Expression Regulation, Plant , Helianthus/enzymology , Helianthus/metabolism , Hexosyltransferases/metabolism , Molecular Sequence Data , Plants, Genetically Modified , RNA, Messenger/analysis , RNA, Plant/analysis , Recombinant Fusion Proteins , Sequence Analysis, DNA , Sequence Homology, Amino Acid
18.
Nat Biotechnol ; 16(9): 843-6, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9743117

ABSTRACT

We have transformed sugar beet into a crop that produces fructans. The gene encoding 1-sucrose:sucrose fructosyl transferase (1-SST), which was isolated from Helianthus tuberosus, was introduced into sugar beet. In H. tuberosus, 1-SST mediates the first steps in fructan synthesis through the conversion of sucrose (GF) into low molecular weight fructans GF2, GF3, and GF4. In the taproot of sugar beet transformed with the 1-sst gene, the stored sucrose is almost totally converted into low molecular weight fructans. In contrast, 1-sst expression in the leaves resulted in only low levels of fructans. Despite the storage carbohydrate having been altered, the expression of the 1-sst gene did not have any visible effect on phenotype and did not affect the growth rate of the taproot as observed under greenhouse conditions.


Subject(s)
Chenopodiaceae/metabolism , Fructans/metabolism , Plant Proteins , Carbohydrates/analysis , Chenopodiaceae/genetics , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Chromatography, Thin Layer , Fructans/biosynthesis , Hexosyltransferases/genetics , Plants, Genetically Modified
19.
Eur J Neurosci ; 9(2): 306-18, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9058051

ABSTRACT

Recently we have shown that biglycan, a small chondroitin sulphate proteoglycan of the extracellular matrix, supports the survival of cultured neurons from the developing neocortex of embryonic day 15 rats. Here we investigate the structure-function relationship of this neurotrophic proteoglycan and show that chondroitin/dermatan sulphate chains are the active moieties supporting survival. Heparin, a highly sulphated glucosaminoglycan, is less active than the galactosaminoglycans (chondroitin-4-sulphate, chondroitin-6-sulphate and dermatan sulphate), whereas hyaluronic acid, an unsulphated glucosaminoglycan, does not support neuron survival. Galactosaminoglycans must be in direct contact with neurons to cause survival. Experiments with elevated potassium concentrations and antagonists of voltage-gated calcium channels exclude the involvement of membrane depolarization. However, genistein and an erbstatin analogue, which are inhibitors of tyrosine kinases with low specificity, abolished neuron survival in the presence of chondroitin/dermatan sulphate, whereas a selective inhibitor of neurotrophin receptor kinases (K252a) had no suppressive effect. Thus, yet unidentified tyrosine kinases are involved in the chondroitin/dermatan sulphate-dependent survival of neocortical neurons. In the embryonic stages of rat neocortical development chondroitin sulphate is mainly located in layers I, V and VI and the subplate. Chondroitin sulphate expression is maintained after birth, extends up to cortical layer IV on postnatal day 7, and is down-regulated until postnatal day 21 concomitant with the period of naturally occurring cell death. The latter observation is consistent with a putative role of chondroitin sulphate in the control of neuron survival during cortical histogenesis.


Subject(s)
Cerebral Cortex/physiology , Chondroitin Sulfates/physiology , Dermatan Sulfate/physiology , Animals , Antibodies, Monoclonal , Calcium Channels/physiology , Cell Survival/physiology , Cerebral Cortex/cytology , Cerebral Cortex/embryology , Chondroitin Sulfates/chemistry , Colorimetry , Dermatan Sulfate/chemistry , Embryo, Mammalian/physiology , Gestational Age , Immunohistochemistry , Ion Channel Gating , Protein-Tyrosine Kinases/antagonists & inhibitors , Rats , Structure-Activity Relationship
20.
Brain Res Mol Brain Res ; 41(1-2): 65-73, 1996 Sep 05.
Article in English | MEDLINE | ID: mdl-8883935

ABSTRACT

Astrocyte-conditioned medium (ACM) supports the survival of rat E15 neocortical neurons. Using a microtiter assay for neuronal survival, we demonstrated that part of the survival activity is associated with a proteoglycan fraction obtained after two chromatographic steps: (1) preparative Q-Sepharose anion-exchange chromatography under non-denaturating conditions and (2) MonoQ chromatography in the presence of 8 M urea. Analytical SDS-polyacrylamide gradient gel electrophoresis of pooled active MonoQ-fractions (MQ-pool) revealed a broad proteoglycan band migrating with an apparent M(r) in the range of 150-400 kDa. Digestion of the MQ-pool with chondroitin-ABC-lyase yielded a major core protein of 50 kDa. In Western blots the high molecular weight (150-400 kDa) material as well as the 50 kDa core protein band were immunoreactive to chicken polyclonal antibodies raised against purified biglycan from rat meningeal fibroblasts. Northern blot analysis of total RNA prepared from highly enriched astrocyte cultures revealed a single 2.9 kb biglycan transcript. By using in situ hybridization we demonstrated that essentially all cells in these cultures expressed biglycan mRNA. Furthermore, highly purified biglycan from bovine cartilage was shown to markedly enhance survival of rat neocortical neurons. In conclusion, we have shown that astrocytes synthesize and release the small chondroitin/dermatan sulfate proteoglycan (CS/DSPG) biglycan, a molecule that was found to support survival of neocortical neurons in vitro.


Subject(s)
Astrocytes/metabolism , Nerve Tissue Proteins/biosynthesis , Neurons/cytology , Proteoglycans/biosynthesis , Animals , Animals, Newborn , Antibody Specificity , Biglycan , Blotting, Western , Cattle , Cell Survival , Cells, Cultured , Chickens , Chromatography, High Pressure Liquid , Chromatography, Ion Exchange , Culture Media, Conditioned/pharmacology , Electrophoresis, Polyacrylamide Gel , Extracellular Matrix Proteins , In Situ Hybridization , Meninges/cytology , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/immunology , Nerve Tissue Proteins/isolation & purification , Nerve Tissue Proteins/pharmacology , Neurons/drug effects , Polymerase Chain Reaction , Protein Denaturation , Proteoglycans/genetics , Proteoglycans/immunology , Proteoglycans/isolation & purification , Proteoglycans/pharmacology , RNA, Messenger/biosynthesis , Rats , Rats, Wistar
SELECTION OF CITATIONS
SEARCH DETAIL
...